1. Field of the Invention
The present invention relates generally to power supplies and, more specifically, the present invention relates to trimming a power supply for increased accuracy in the maximum deliverable power of the power supply.
2. Background Information
Most battery operated portable electronic products such as cell phones, personal digital assistants (PDAs), etc., require a low power alternating current (AC) to direct current (DC) charger power supply with a constant voltage and constant current (CC/CV) characteristics for charging batteries. In known power supplies, the peak current limit threshold and operating frequency are trimmed independently during manufacturing. The two parameters have their own specifications without any relationship to each other. Other known power supplies employ discrete solutions where the tolerances of components like resistors, and capacitors will affect the peak current limit threshold, and the operating frequency, and by doing so also affecting the maximum delivered power.